We all know Lance Sweets is a master of psychoanalyzing, but when Booth finds himself sidelined in tonight’s episode of Bones, Sweets is going to step out from behind his desk to prove himself unlike ever before.

“Booth is unavailable in this portion of the series because he’s prepping the episode that follows to direct,” jokes John Francis Daley, referencing star David Boreanaz’s turn as director for the season finale. “The way they wrote it is that he’s busy studying for this FBI exam and he hands the reigns over to Sweets to be the lead FBI agent on the case and, of course, Sweets jumps at the opportunity.”

Sweets’ by-the-book ways, however, prove to be more of a detriment than a benefit, says Daley. And further complicating matters is new squintern Jessica Warren (Jessica Weaver), who quickly discovers some key ways to ruffle Sweets’ feathers. (Watch an exclusive clip below.) “I think the level of enthusiasm he had when he got his first gun kind of shows that Sweets likes to be as involved in the action as he can,” says Daley. “And for me, it’s definitely fun to be able to go from the strictly psychoanalyst role to someone who’s more broad in the field.”

“I don’t know how much he’s going to be doing that in the next season,” he says, adding with a laugh, “probably a lot in the episodes before the ones that David directs.”

Speaking of the Boreanaz-directed finale, it’s a big one and possibly one of the show’s most ambitious action episodes yet. “This one is literally explosive,” he says. “The way David directed it was with a focus on people being very intense because we’re dealing with some heavy stuff. So it was fun to play it as the stakes were higher than ever. It was almost like filming an episode of 24 in that sense. Every scene is high-stakes.”